1. Field of the Invention
The present invention relates generally to a method of integrating the data of an Extensible Markup Language (XML) document with a database (DB) on a web and, more particularly, to a method of integrating the data of an XML document with a DB on a web, which can dynamically integrate the data of an XML document with a DB on a web using an XML replacement technology.
2. Description of the Related Art
Generally, markup language refers to a series of characters or symbols inserted into specific locations so as to reveal a way in which a relevant file is to be output through a printer or a form in which the file is to be viewed on a screen. Well-known markup languages include Standard Generalized Markup Language (SGML) and HyperText Markup Language (HTML).
SGML is a markup language mainly for efficiently transmitting, storing and automatically processing multimedia electronic documents between different heterogeneous systems without causing the loss of information. HTML is a markup language mainly for describing hypermedia documents used on the Internet.
SGML is disadvantageous in that even if it has various functionalities, as described above, it is difficult to use the SGML and it is not easy to generate and understand a document type definition (hereinafter referred to as “DTD”). Further, HTML is disadvantageous in that even if it is simple and is easily used, HTML is a fixed markup language defined by SGML, and thus it is difficult to incorporate the variety of and dynamic characteristics of the web.
In order to compensate for the disadvantages of existing markup languages, an extensible markup language (hereinafter referred to as “XML”) has been proposed. XML is a next generation Internet standard language proposed by the World Wide Web Consortium (W3C) in 1996 and adopted as a recommended standard by the W3C in the spring of 1998.
XML is a meta-language generated by improving the simple representational functions of HTML, collecting only the practical functions of SGML and then simplifying them. This XML is one of Internet standard languages that are currently receiving attention thanks to its various advantages such as the advantage of having excellent compatibility with other languages, being easy to create, and having a DTD for verifying a data format and tools for supporting the DTD, and the advantage of a tag being closely related to the contents of a document so that an XML file itself may function as a single desirably designed DB.
That is, to date, HTML which has been most widely used as a content representation language on the Internet, is suitable for the functionality of representation, but has limitations when desiring to reuse or search for documents. Thus, as a next-generation Internet language for solving these limitations, XML that is a language enabling the scalability, compatibility, and information structurization has received attention.
Meanwhile, a database (DB) is a structure of data stored depending on specific relationships that reflect the meaning of data. Such a DB, as storage of information, is used by a large number of application programs, and thus the structure of a DB must be able to be changed without the revision of application programs.
In the prior art, there are problems in that a DB must be newly created to store XML documents in the DB, and XML documents having the same DTD must be stored in the table of the newly created DB, and in that when, in particular, the schema structures of DBs storing XML documents are different from one another, the data of an existing DB may not be used, or the data of the existing DB that has already been constructed must be migrated to the new DB.
In order to solve these problems, research has been conducted into technology in which the information of a DB is converted into a document using XML and the document represented by XML is stored easily in the DB, by generating mapping rules between the DTD of the XML document and the schema of the DB, converting the XML document into the DB in compliance with the generated mapping rules and then storing the DB, and by converting information stored in the form of the DB back into the XML document.
In detail, technology entitled “method of storing and managing an XML document and a medium for storing software programmed to perform the same” is disclosed in Korean Patent Application No. 10-2001-0017631. This patent proposes a method of storing and managing an XML document, which performs mapping between the schema structure of a DB that has been previously constructed and used and DTD documents defining the structure of an XML document, thus performing storage and searching in conjunction with even the DB of schema types that were used previously.
Further, in the prior art, as the requirements of users related to application programs are diversified, there are a large number of types and quantities represented by XML documents, so that there is a problem in that it is difficult for a system, in which a single DB server processes the requests of all users, to promptly cope with the requests of the users to make a response.
In order to solve this problem, research has been conducted into technology which enables pieces of XML data managed by a source DB to be duplicated to another server which is physically different from a source server without any loss of the meanings of structural information and attribute information contained in an original XML document as well as the contents of the original XML document.
In detail, technology entitled “apparatus and method for duplicating an XML document to a remote server without any loss of the structural and attribute information of the XML document” is disclosed in Korean Patent Application No. 10-2003-0092525. This patent proposes a method which can process the service requests of application programs by distributing users' queries that have been concentrated on a source server into a plurality of duplication servers while allowing even each duplication server to support searching based on the contents and attributes provided by an XML query language, through the use of characteristics of the structural and attribute information included in each XML document being maintained without change when duplicating the XML document stored in the DB of the source server to the DB of the duplication server.
However, the above patents are problematic in that promptness is low when the data of each XML document is stored in the DB and in that when errors are caused in a storage procedure, a DB having low accuracy may be constructed. Therefore, the inventor of the present invention has completed the invention related to a scheme capable of immediately integrating an XML document on a web with a DB using mapping information upon integrating data while conducting research into technology for integrating data with a DB using data mapping between XML/Extensible Stylesheet Language (XSL) documents so as to solve the above problem.